Anne Vibeke Mou has suspended a cloud on glass. By means of carefully calibrated blows of a metal point, she has punched hundreds and thousands of minute marks into its hard surface and, with the others that she generated over her months of work, these combine to form a roiling mass moving across the window set into the wall of St John’s Church, Healey. Each tiny opaque star made by the shock of the blow is analogous to the drops of water vapour, which, with millions of others, constitute the clouds that move and recombine in the skies above us.

In the glass, however, the movement is frozen. Instead of a cloud transforming itself through the constant shift of droplets of water in relation to each other, here changes in density and form are determined by where the viewer stands and the angle and intensity of light to the minute opacities in the glass. Sometimes the cloud will become fugitive and imperceptible, other times the window will be filled by its unfolding waves. There will be moments when it will almost disappear – perhaps when the interior chamber has been made dark by bright sunlight – other times when it will seem entirely present: maybe when it is night outside and the viewer is looking up from the brightness within. Each change will be shaped by the relationship of the viewer to the glass, the angle of the glass to the sun, by the shift of the ecliptic and the movement of the planet through the heavens.

Mou’s project is informed by minimalism, an aesthetic based upon reduction and the exploration of the nature of materials. The matter and manner of an artwork’s construction becomes, in many ways, the content of that work. Here, for instance, Mou is using no coloured glass, no insets, no cast details. Her range of effect is determined by what happens to the surface of the specially made glass slab under the pressure of a point . From this simple, direct, genesis she has created an image of extraordinary complexity. Similar approaches have informed previous work. She has shown old panes of glass abstracted from their usual context – the window-frames of old buildings – and put them on display in the pristine white space of the art gallery. So we had to interrogate each wave and bump, imagine what events might have unfolded on either side of the plane: the glass became a crystalisation of time and its processes. Another significant strand in her work has been the development of large drawings, using pencil on paper, where the constant repetition of a small mark has built up the graphite into grey clouds and masses, which might be sublime images of distant star dust or mysterious close ups of matter made gigantic through microscopes. Freezing the transitory processes of change, her work here unites these two lines of investigation into a single work.

The approaches of minimalism not only make the viewer sensitive to the subtleties of the object in front of them, they heighten awareness of the space that contains the work, how interactions between the work, the volumes that surround it and the viewer shape our understanding. This happens in the white anodyne modernist cube of an art gallery but when the context for a work is the chamber of a church, implication and association multiply exponentially. Although these approaches are rooted in the material, there is a profound engagement with the idea of essence, so an immaterial realm is conjured into being: a Platonic realm, where the pure unsullied form exists – the Platonic Ideal – rather than the imperfect one that we experience on this physical plane. The work embodies and echoes the functions of the spaces that contain it.

Glass itself moves between the material and the immaterial – it is solid yet nearly not there – and between physical and metaphysical realms. It transforms objects and space: it makes the small seem massive (but give it another shape and this shift is reversed). It changes time: the light from stars in the night sky seen through the lens of a telescope is ancient light, which might have been travelling for billions of years, before arriving here on earth. The stronger the lens, the further away is the past that is pulled into our present. Glass contains time in other ways. In our day-to-day lives we consider the material as fixed and immutable – unless, of course, it is stressed and shatters into fragments and shards – but as every schoolchild learns, this unyielding surface is just a slow liquid, which is inexorably flowing and changing. The opaque points made by the artist in the window here will not shift much in relationship to each other over our lifetime or the lifetimes of generations. But over other vaster measures of time they are as much in motion as the molecules of water vapour that make up the white cumulus and thunderhead.

Marcel Duchamp used glass as a material to slow down time to map the peculiar operations of the Bride and her Batchelor machines in ‘The Bride Stripped Bare by her Bachelors Even’ – also known as the Large Glass – a vast and complex schematic made between 1915 and 1923. The world he was describing took place, he said, in an unfolding multi-dimensional universe, so the glass screens which hold the static image were operating as ‘a delay’ in glass. They held a particular moment abstracted from the multitude of moments that constitutes the life of an act or event that stretched out invisibly on either side of the panes. Almost like a section cut from a plant stem mounted on a microscope slide, but miraculously with no apparent damage.

There was a similar fascination in medieval times as to how glass bridged or mediated dimensions. It was considered mysterious and meaningful that a beam of light from the sun would pass through a pane of glass and shine brightly on the floor, without either the beam being interrupted or the glass broken or changed. This generated a body of optical symbolism and iconography to do with the Virgin and the Incarnation. Glass vessels were often used in painting to symbolize the essential purity of Mary and we are familiar with Renaissance paintings of a throne room – the standard setting for virgin and child paintings – with light coming in through the window. The beam of light signifies the ‘light of the world’, and its passage through the window pane a metaphor for the conception of Christ. As the 15th century hymn ‘Dies est laetitae’ stated ‘ As the sunbeam through the glass passeth but nor staineth, thus the Virgin she was, Virgin still remaineth’.

In this context, the marks that cloud the window’s surface take on a new layer of resonances too. If the pencil drawings touched on ideas of the sublime, here we are inevitably moved towards the numinous. We are reminded of the close and necessary relationship between images of the sublime and representations of the Divine. The Gods often live behind clouds, either on mountaintops or in the empyrean realm. They manifest through clouds – be this Zeus the thunder god, or Jehovah leading Israel out of Egypt in a ‘pillar of a cloud’. He speaks to Moses on Mount Sinai through a cloud and in the Book of Revelation where ‘He cometh with clouds’. There are Clouds of Glory, Clouds of Witnesses, even Clouds of Unknowing.

Anne Vibeke Mou’s window, commissioned for the Church of St John’s, Healey does not illustrate or narrate any of these allusions or stories. Indeed, the work is nearly Puritan in its modesty and its refusal of representation (and its abstraction and restraint serve to echo specific developments to how religious iconography has been imagined in this country). The cloud is not a representation of a cloud; it is a cloud, made of marks on a weighty pane of glass set into the wall of a place that – as Philip Larkin wrote – ‘is a serious place on the serious earth’. The beauty of the work – both physically and metaphorically – is how it illuminates this. It seems to voice and express profound narratives and ideas, which also are contained in this ‘serious place’, about the ways that we variously seek to understand the world and the realms that contain our world. It does this, and, at the same time, remains resolutely of itself.